1. Field of the Invention
The present invention relates generally to hydraulic cylinder assemblies, and more particularly to a hydraulic cylinder assembly that may be used in variable external pressure environments such as found on a submersible vehicle.
2. Description of the Prior Art
Commercially available hydraulic cylinders generally are designed to accommodate high internal pressure and, thus, are configured with seals designed to withstand such internal pressure. However, if used in an undersea, or other high external pressure environment, the seals tend to fail inwardly. Even if a commercially available hydraulic cylinder were adjusted to accept seawater as the operating fluid, problems related to material corrosion and seal contamination would likely develop. Thus, commercially available hydraulic cylinders are not currently considered for variable depth, deep sea applications. In deep sea applications, high cost, specially designed hydraulic cylinders are the only cylinders available.